1b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper/* Get information from dynamic table at the given index. 21ccdfb683ad6c7e59793136c3a657ddf131cafd1Mark Wielaard Copyright (C) 2000, 2001, 2002, 2005, 2009, 2014, 2015 Red Hat, Inc. 3de2ed97f33139af5c7a0811e4ec66fc896a13cf2Mark Wielaard This file is part of elfutils. 4b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper Written by Ulrich Drepper <drepper@redhat.com>, 2000. 5b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 6de2ed97f33139af5c7a0811e4ec66fc896a13cf2Mark Wielaard This file is free software; you can redistribute it and/or modify 7de2ed97f33139af5c7a0811e4ec66fc896a13cf2Mark Wielaard it under the terms of either 8b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 9de2ed97f33139af5c7a0811e4ec66fc896a13cf2Mark Wielaard * the GNU Lesser General Public License as published by the Free 10de2ed97f33139af5c7a0811e4ec66fc896a13cf2Mark Wielaard Software Foundation; either version 3 of the License, or (at 11de2ed97f33139af5c7a0811e4ec66fc896a13cf2Mark Wielaard your option) any later version 12de2ed97f33139af5c7a0811e4ec66fc896a13cf2Mark Wielaard 13de2ed97f33139af5c7a0811e4ec66fc896a13cf2Mark Wielaard or 14de2ed97f33139af5c7a0811e4ec66fc896a13cf2Mark Wielaard 15de2ed97f33139af5c7a0811e4ec66fc896a13cf2Mark Wielaard * the GNU General Public License as published by the Free 16de2ed97f33139af5c7a0811e4ec66fc896a13cf2Mark Wielaard Software Foundation; either version 2 of the License, or (at 17de2ed97f33139af5c7a0811e4ec66fc896a13cf2Mark Wielaard your option) any later version 18de2ed97f33139af5c7a0811e4ec66fc896a13cf2Mark Wielaard 19de2ed97f33139af5c7a0811e4ec66fc896a13cf2Mark Wielaard or both in parallel, as here. 20de2ed97f33139af5c7a0811e4ec66fc896a13cf2Mark Wielaard 21de2ed97f33139af5c7a0811e4ec66fc896a13cf2Mark Wielaard elfutils is distributed in the hope that it will be useful, but 22361df7da6dfecd817b27e62b91752ac316d7cdd4Ulrich Drepper WITHOUT ANY WARRANTY; without even the implied warranty of 23361df7da6dfecd817b27e62b91752ac316d7cdd4Ulrich Drepper MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 24361df7da6dfecd817b27e62b91752ac316d7cdd4Ulrich Drepper General Public License for more details. 25b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 26de2ed97f33139af5c7a0811e4ec66fc896a13cf2Mark Wielaard You should have received copies of the GNU General Public License and 27de2ed97f33139af5c7a0811e4ec66fc896a13cf2Mark Wielaard the GNU Lesser General Public License along with this program. If 28de2ed97f33139af5c7a0811e4ec66fc896a13cf2Mark Wielaard not, see <http://www.gnu.org/licenses/>. */ 29b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 30b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper#ifdef HAVE_CONFIG_H 31b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper# include <config.h> 32b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper#endif 33b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 34b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper#include <assert.h> 35b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper#include <gelf.h> 36b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper#include <string.h> 37b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 38b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper#include "libelfP.h" 39b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 40b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 41b08d5a8fb42f4586d756068065186b5af7e48daUlrich DrepperGElf_Dyn * 421ccdfb683ad6c7e59793136c3a657ddf131cafd1Mark Wielaardgelf_getdyn (Elf_Data *data, int ndx, GElf_Dyn *dst) 43b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper{ 44b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper Elf_Data_Scn *data_scn = (Elf_Data_Scn *) data; 45b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper GElf_Dyn *result = NULL; 46b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper Elf *elf; 47b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 48b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper if (data_scn == NULL) 49b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper return NULL; 50b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 51b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper if (unlikely (data_scn->d.d_type != ELF_T_DYN)) 52b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper { 53b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper __libelf_seterrno (ELF_E_INVALID_HANDLE); 54b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper return NULL; 55b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper } 56b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 57b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper elf = data_scn->s->elf; 58b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 59b4d6f0f8064f2b706ea9035ef0393d8299671390Roland McGrath rwlock_rdlock (elf->lock); 60b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 61b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper /* This is the one place where we have to take advantage of the fact 62b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper that an `Elf_Data' pointer is also a pointer to `Elf_Data_Scn'. 63b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper The interface is broken so that it requires this hack. */ 64b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper if (elf->class == ELFCLASS32) 65b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper { 66b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper Elf32_Dyn *src; 67b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 68b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper /* Here it gets a bit more complicated. The format of the symbol 69b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper table entries has to be adopted. The user better has provided 70b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper a buffer where we can store the information. While copying the 71b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper data we are converting the format. */ 72a9039623c272f458a53f09009c2a0e1d6e60491dJakub Jelinek if (INVALID_NDX (ndx, Elf32_Dyn, &data_scn->d)) 73b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper { 74b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper __libelf_seterrno (ELF_E_INVALID_INDEX); 75b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper goto out; 76b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper } 77b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 78b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper src = &((Elf32_Dyn *) data_scn->d.d_buf)[ndx]; 79b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 80b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper /* This might look like a simple copy operation but it's 81b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper not. There are zero- and sign-extensions going on. */ 82b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper dst->d_tag = src->d_tag; 83b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper /* It OK to copy `d_val' since `d_ptr' has the same size. */ 84b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper dst->d_un.d_val = src->d_un.d_val; 85b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper } 86b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper else 87b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper { 88b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper /* If this is a 64 bit object it's easy. */ 89b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper assert (sizeof (GElf_Dyn) == sizeof (Elf64_Dyn)); 90b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 91b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper /* The data is already in the correct form. Just make sure the 92b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper index is OK. */ 93a9039623c272f458a53f09009c2a0e1d6e60491dJakub Jelinek if (INVALID_NDX (ndx, GElf_Dyn, &data_scn->d)) 94b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper { 95b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper __libelf_seterrno (ELF_E_INVALID_INDEX); 96b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper goto out; 97b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper } 98b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 99b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper *dst = ((GElf_Dyn *) data_scn->d.d_buf)[ndx]; 100b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper } 101b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 102b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper result = dst; 103b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 104b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper out: 105b4d6f0f8064f2b706ea9035ef0393d8299671390Roland McGrath rwlock_unlock (elf->lock); 106b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper 107b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper return result; 108b08d5a8fb42f4586d756068065186b5af7e48daUlrich Drepper} 109